package devices

import (
	"context"
	"xiaomihome/xiaomi"
)

// Cover 窗帘/晾衣架统一控制接口
type Cover interface {
	Device
	Open(ctx context.Context) error
	Close(ctx context.Context) error
	Stop(ctx context.Context) error

	SetPosition(ctx context.Context, pct int) error // 0=关, 100=全开
	GetPosition(ctx context.Context) (int, error)
}

type coverDevice struct {
	BaseDevice
	propMotor    siidPiid // "motor-control" — open/close/stop
	propPosition siidPiid // "current-position"
}

const (
	coverMotorOpen  = 1
	coverMotorClose = 0
	coverMotorStop  = 2
)

// NewCover creates a Cover control for the given device.
func NewCover(client *xiaomi.Client, info *xiaomi.DeviceInfo) (Cover, error) {
	d := &coverDevice{
		BaseDevice: NewBaseDevice(client, info),
	}

	resolver := d.getSpecResolver()
	if resolver == nil {
		return nil, xiaomi.ErrNoSPEC
	}

	siid, piid, ok := resolver.find("motor-control")
	if !ok {
		return nil, xiaomi.ErrNotSupported
	}
	d.propMotor = siidPiid{siid, piid, true}

	if s, p, ok := resolver.find("current-position"); ok {
		d.propPosition = siidPiid{s, p, true}
	}

	return d, nil
}

func (d *coverDevice) Open(ctx context.Context) error {
	if !d.propMotor.valid {
		return xiaomi.ErrNotSupported
	}
	return d.SetProp(ctx, d.propMotor.siid, d.propMotor.piid, coverMotorOpen)
}

func (d *coverDevice) Close(ctx context.Context) error {
	if !d.propMotor.valid {
		return xiaomi.ErrNotSupported
	}
	return d.SetProp(ctx, d.propMotor.siid, d.propMotor.piid, coverMotorClose)
}

func (d *coverDevice) Stop(ctx context.Context) error {
	if !d.propMotor.valid {
		return xiaomi.ErrNotSupported
	}
	return d.SetProp(ctx, d.propMotor.siid, d.propMotor.piid, coverMotorStop)
}

func (d *coverDevice) SetPosition(ctx context.Context, pct int) error {
	if !d.propPosition.valid {
		return xiaomi.ErrNotSupported
	}
	return d.SetProp(ctx, d.propPosition.siid, d.propPosition.piid, pct)
}

func (d *coverDevice) GetPosition(ctx context.Context) (int, error) {
	if !d.propPosition.valid {
		return 0, xiaomi.ErrNotSupported
	}
	prop, err := d.GetProp(ctx, d.propPosition.siid, d.propPosition.piid)
	if err != nil {
		return 0, err
	}
	return toInt(prop.Value), nil
}